Table 3.

Reference doses (RfDs) for selected metals (USEPA/WHO)^35,37.

Metal	RfD, mg/kg/day	Source
As	0.0003	USEPA
Cd	0.001	USEPA
Pb	0.0035	WHO/USEPA
Cu	0.04	WHO
Fe	0.7	WHO
Mn	0.14	WHO
Mo	0.005	USEPA
Ni	0.02	USEPA
Zn	0.3	WHO